Cytologic studies on so-called atypical epithelium of the protuberant lesions in the stomach.

Cytologic studies based on the observation of 32 atypical epithelial growths from 31 patients revealed the following characteristics: (1) The nuclei were usually elongated. The mean size of the major axis of the nuclei was most frequently distributed in the range of from 14 to 17mu while the mean size of the minor axis was between 6 and 10mu. (2) The chromatins of the nuclei were fine and showed even to somewhat dense distribution. The nucleolus was inconspicuous. (3) The cells were heaped together. A cellular aggregation was clearly composed of smaller groups of cells in which the polarity of nuclear arrangement was well preserved. Some cells at the periphery of a cellular aggregation were arranged radially toward the outside. The cells were usually cohesive, but in severe grade of atypism, they sometimes showed a scattering tendency. (4) The cells of atypical epithelium seemed to be very insensitive to radiation, compared with carcinoma cells of the stomach.